It has been the trend to scale down the sizes of memory cells to increase the integration level and thus memory capacity of a DRAM chip. As the size of DRAMs is decreased, the capacity of the capacitor used in the DRAM is correspondingly decreased.
A memory cell of DRAM typically consists of a storage capacitor and an access transistor. With the advent of large-scale integrated DRAM devices, the size of the devices has gotten smaller and smaller such that the available area for a single memory cell has become very small. This causes a reduction in the capacitor's area, resulting in the reduction of the cell's capacitance.
Prior art methods for manufacturing a capacitor with increased area include methods for manufacturing stack capacitors and crown capacitors. However, it is desirable to have a new method for manufacturing a capacitor with even more area and with a structure that is stronger than previous crown capacitors.